Sadly, I think the problems stem from a lack of informed thinking. When the road was constructed, with the associated drainage, it would have been designed to withstand a 1 in 100 year weather event. That's pretty standard, even now. There's a general lack of acceptance that the climate is changing and a complete lack of understanding about the effects of that change, the major one of which is to increase the frequency of severe weather events.
A good example of this is the Marine drive around the Orme. One of the contributory factors behind the flooding in 1993 was that the road has a wall around it which acts - for all intents and purposes - as a gutter. In Florida, where torrential rain is the norm, the drain cavities are enormous, so they don't have flooding as such. It would have cost relatively little to insert large openings in the wall and the rock face sides, so that were another event such as the 1993 storm to repeat itself, Llandudno would survive the event much better. But no: in their collective wisdom the various councils have decided that such an event won't reoccur for another hundred years.
Guess what...
